#include <stdio.h>
int main()
{
	int a, b, c;
	scanf_s("%d%d%d", &a, &b, &c);
	if (a + b > c && b + c > a && a + c > b)
	{


		if (a == b && a == c)
		{
			printf("Equilateral triangle!");
		}
		else if (a == b || b == c || a == c)
		{
			printf("Isosceles triangle!");
		}
		else
		{
			printf("Ordinary triangle!");
		}
	}
	else
	{
		printf("Not a triangle!");
	}
	return 0;
}